Method of making integral fan and slinger ring



June 22, 1965 K. A. MERZ 3,139,982

METHOD OF MAKING INTEGRAL FAN AND SLINGER RING Filed 001;. s, 1961 2Sheets-Sheet 1 INVENTOR. v .KENNETH A. MERZ A TTORNE Y5 June 22, 1965 K.A. MERZ 3,189,982

METHOD OF MAKING INTEGRAL FAN AND SLINGER RING Filed Oct. 5, 1961 2Sheets-Sheet 2 FIG 3 United States Patent 3,189,982 METHGD 6F MAKltNGFNTEGRAL FAN ANFJ SlLltNGER RiN-G Kenneth A. Mara, Qornwall, Conn,assigner to The Torrington h'lanufactnring Company, Torrington, Conn, acorporation of (Ionneetieut Filed Diet. 3, 1951, Ser. No. M2,,d39Claims. (till. 29-4568) This invention relates to an integral fan andslinger ring of the type wherein a hub section of the fan is oifsetaxially with respect to the slinger ring and, more particularly, theinvention relates to a method of making such a fan and slinger ring.

It is the general object of the invention to provide a method ofproducing a fan and slinger ring of the type mentioned wherein the needfor expensive blanking and drawing tools is eliminated and a substantialeconomic advantage in manufacture is achieved.

The drawings illustrate structure specific to three forms of the methodof the invention, but it will be understood that various changes may bemade from the structure shown and the method forms described, and thatthe drawlugs and description are not to be construed as defining orlimiting the scope of the invention, the claims forming a part of thespecification being relied upon for that purpose.

Of the drawings:

FIG. 1 is a plan View of an intermediate blank formed in accordance withthe method of the present invention;

FIG. 2 is a side elevation of a completed integral fan and slinger ringproduced in accordance with the method of the invention;

PEG. 3 is an enlarged fragmentary section taken generally as indicatedat 3-3 in FIG. 1 and showing a portion of a fan blade, a connecting tab,and a slinger ring, back ground parts being omitted:

FIG. 4 is an enlarged fragmentary section similar to FIG. 3, but showingthe tab in a preformed condition;

FIG. 5 is an enlarged fragmentary section similar to F163. 3 and 4, butshowing the parts completed;

FIG. 6 is an enlarged fragmentary section similar to FIG. 4, but showinga tab performed in accordance with a second form of the method of theinvention;

FIG. 7 is an enlarged fragmentary plan view showing a tab formed andarranged in accordance with still another form of the method of theinvention; and

FIG. 8 is an enlarged fragmentary section taken generally as indicatedat 8-8 in FIG. 7. i

It has heretofore been a conventional practice to form an integral fanand slinger ring of the type referred to by providing a flat circularblank and forming the same into a conical configuration as in a drawingoperation. Subsequently, as in a blanking operation, selected portionsof the conical blank have been severed to define the various elements ofthe fan and slinger ring and, finally, the necessary forming has beenaccomplished to provide an annular flange on the slinger ring and topitch the blades. This method is capable of producing a satisfactoryintegral fan and slinger ring, but the method has not been economicallyadvantageous. Drawing tools required to form the cone and blanking toolssuitable for operation on a conical blank are extremely expensive. In afact, the costs encountered have been so excessive as to Patented June.22, 1965 prevent the manufacture of this type of fan in low quantityproduction.

In the practice of the method in the present invention, the need forexpensive drawing and blanking tools is elimihated and a substantialeconomic advantage is achieved in both low and high quantity production.In general, the method of the invention comprises the steps of providinga one-piece sheet metal blank which has selected portions severedtherefrom so as to define all of the elements of the fan and slingerring in connected relationship, but in substantially flat form. Thus,blanking can be accomplished at low cost on a fiat rather than acone-shaped blank. In order that subsequent forming of the blank topitch the blades and to offset the hub section may be accomplishedwithout excessive deformation and/ or rupture of the said elements, theflat blank is provided with at least one annular area wherein the fanelements or portions thereof are arranged so as to have dimensionsbetween inner and out r boundaries of the area which are greater thanthe radial distance between the boundaries. in forming of the blankwhich effects pitching of the blade and the axial offset relationship ofthe hub section, the differences between the interboundary dimensions ofthe said elements or portions thereof and the radial distance betweenboundaries are employed to accommodate axial movement of the hub sectionrelative to the slinger ring. Thus, a particular arrangement of elementsor portions thereof in a selected annular area on the blank accommodatesthe necessary movement for the final offset arrangement of the hubsection and the necessity of providing an intermediate conical blank andthe costs attendant upon the provision of such a blank are whollyeliminated.

Referring now particularly to FIG. 2, it will be observed that acompleted fan and slinger ring shown therein comprises a plurality ofsimilarly pitched and circumaxially spaced air moving blades ill, 10.Five blades 10, 10 are shown, but the method of the invention is equallyadaptable to the production of fan and slinger ring assemblies withvarious numbers of blades. The blades it], 10 are comparatively broadthroughout major portions of their lengths, but relatively narrow innerpants 12, 12 thereof have their inner edge portions connected with andformed integrally with a hub section 14. The hub section 14 is offsetaxially with respect to an integral slinger ring 16 which includes anannular flange 18 extending in an axial direction from its outer edge.The slinger ring 316 is disposed about the blades til, it as shown andis connected thereto by means of small connecting tabs 20, 20 extendingbetween said ring and outer edge portions of the blades. Outer endportions of the tabs 20, 2t) lie substantially in the plane of theslinger ring is, but inner edge portions thereof are slightly twistedin. keeping with the pitch of the blades it ill, FIG. 5.

Referring now to FIG. 1, it will be observed that a blank shown thereinhas selected portions severed therefrom so as to define all of theelements of the completed fan and slinger ring in connectedrelationship. The said elements are, however, defined in a fiat form. Aflat hub section 14 of the blank is connected with inner parts 12, 12 offlat blades ill, 10 which are in turn connected with a planar slingerring section 16 by flat tabs 20, 20. The blank may be provided in aconventional flat blanking operation and may properly be characterizedas an intermediate blank, a fiat circular initial or first blank beingsupplied for the blanking operation.

Now, the selection of a particular annular area on the intermediateblank as well as the manner in which elements or portions of elementsfalling within the boundaries of the area are arranged to provide fordimensions greater than the radial distance between said boundaries mayvary within the scope of the invention. Preferably, however, an annulararea on the blank is selected between the hub section 14 and the slingerring section 16 and is at such location and of such width that it willbound a minimum aggregate mass of metal. Thus, in FIG. 1, an annulararea including the tabs 20, 2% is selected and such area may beidentified by its inner and outer boundaries which are representedrespectively by the broken line 22 and the inner edge 24 of the slingerring section 16. As will be noted, the inner boundary 22 of the arearegisters with the inner edges of the tabs 2t 2% while the outerboundary 24 thereof registers with the outer edges of said tabs.

In a first form of the method, the tabs 2h, 2% are arranged so as tohave dimensions between the boundaries 22 and 24 greater than the radialdistance between said boundaries by displacing at least a portion ofeach tab from the plane of the flat intermediate blank. That is, theintermediate blank is provided as mentioned above by a flat blankingoperation and the tabs 2t 20 are thereafter performed to the desiredarangement of excess dimension.

7 As illustrated in FIG. 3, each tab Ztl has a lengthwise dimension xafter formation of the intermediate blank of FIG. 1. As will beobserved, the dimension x is also equal to the radial distance betweenthe inner and outer boundaries 22 and 24 of the aforesaid annular area.Preforming of the tabs 29, 20 as by drawing with a suitable tool is thenaccomplished to displace at least a portion of each tab from the planeof the blank. As illustrated in FIG. 4, preforming is preferablyaccomplished toprovide for a bowed configuration of each tab 20 viewedin an axial plane. A lengthwise dimension y 4 its center line disposedon a radius.

the intermediate blank to pitch the blades and to axially offset the hubsection of a fan and slinger ring including the tabs 243a, a will resultin stretching and approximate straightening of the tabs to theconfiguration illusrated in FIG. 5. Obviously, excessive deformationand/ or rupture of the tabs or other elements in the fan and slingerring assembly will be positively avoided.

A third form of the method of the present invention involves theprovision of tabs of the type shown at 2% in FIG. 7. The tab Ztib isflat as illustrated in FIG. 8 and extends in an intermediate blank suchas shown in FIG. 1 between a blade 10]) and a slinger ring section 16b.The tab does not, however, extend along or have Instead, the tab isinclined with respect to all radii and with respect to all axial planes.Thus, the tab 2% has a lengthwise dimension y in excess of a dimension xthe dimensioin x being measured along a radius and between inner andouter boundaries 22b and 24b of a selected annular area of the tabs 20measured arcuately then exceeds the former lengthwise dimension x of thetabs and accordingly exceeds the radial distance between the boundaries22 and 24 of the selected angular area.

- The amount by which the dimension y exceeds the dimension x may varywithin the scope of the invention. However, preforming of the tabs 20,20 is preferably accomplished so that their dimension y is substantiallyequal to a dimension 2: illustrated in FIG. 5. As will be observed, thedimension 2 represents the length of the tabs 20, 20 in the completedfan and slinger ring assembly. That is, the preformed tabs 20, 2th ofFIG. 4 are stretched so as to be approximately straightened in thesubsequent forming operation of pitching the blades 10, 10 and movingthe hub section 14 to its axially offset position. the tabs 20, 20accommodates the necessary axial movement of the hub section 14 relativeto the slinger ring 16 without excessive deformation and/or tearing ofthe tab as previously mentioned.

In FIG. 6 it will be observed that a tab 2 41a has a corrugated crosssection in an axial plane. The said tab is preformed to'such shape inthe practice of a second form of the method of the invention. In thesaid sec- 0nd form of the method, a circular initial or first Suchstretching and approximate straightening of blank may be operated on ina blanking operation to form the fiat intermediate blank of FIG. 1 asdescribed above. Thereafter, each of the tabs 24M, Ztla of theintermediate blank may be preformed to the corrugated cross section ofFIG. 6 as in a suitable drawing operation.

Here again, the initial lengthwise dimension 2: of the tabs iseffectively increased to exceed the radial distance between theboundaries 22a and 24a of an annular area selected as described above.An arcuate lengthwise dimension y of the preformed tabs Ztia, Ztiaapproximately equals the aforesaid arcuate lengthwise dimension y of thepreformed tabs 20, 20. Thus, subsequent forming of which includes thetab 2% and corresponding tabs not shown. Thus, a dimensional excess isprovided to ac- 'commodate axial movement of a hub section relative tothe slinger ring section 16b without excessive deformation or rupture ofthe tab Ztlb shown and corresponding tabs.

In practicing the third form of the method, the inclined arrangement ofthe tabs 20b, 26b for excess dimension is provided in a blankingoperation which produces a flat intermediate blank similar to that shownin FIG. 1. Thereafter, and during the forming operation which effectspitching of the blades and axial movement of the hub section, relativerotation is effected between the slinger ring section 1617 and theblades 1%, 10b to arrange the longitudinal center lines of the tabs20]), 20b at least approximately in axial planes. Such relative rotationeffectively elongates the tabs 20b, 20b so that the required axial hubsection movement is accommodated without deformation or rupture of thetabs or other elements of the fan and slinger ring assembly. Arrows 26,26 in FIG. 7 indicate the direction of relative rotation of the fanblades and slinger ring for the tab 20b shown.

Formation of the flange 18 on the fan and slinger ring is not criticalin the practice of the method of the present invention. Irrespective ofthe form of the method practiced, the flange 18 may be formed at variousstages in the manufacture of the fan and slinger ring. As one example,it will be noted that a drawing operation may be accomplished prior toformation of the intermediate blank.

Now from the foregoing it will be apparent that conventional andinexpensive cutting and forming tools can be employed in the practice ofeach form of the method of the present invention. Blanking can beaccomplished on a flat initial or first blank or workpiece and the expense of providing blanking tools operable on a conical blank is whollyavoided. Expensive drawing tools for providing a conical blank are alsoobviously unnecessary. Moreover, light drawing tools operable on a flatintermediate blank to provide the bowed or corrugated tabs of FIGS. 4and 6 may be of a comparatively simple and inexpensive design.Similarly, a tool rotating means for effecting relative rotation duringforming with the tabs 20b, Zfib is readily provided at low cost.

The invention claimed is:

1. A method of making an integral fan and slinger ring which includes aplurality of similarly pitched circumaxially spaced air moving blades, aslinger ring disposed about the blades, a plurality of connecting tabsextending respectively between outer edge portions of the blades and theslinger ring, and a hub section substantially offset axially withrespect to the tabs and connected with inner edge portions of theblades; said method comprising the steps of providing a one-piece sheetmetal blank which has selected portions severed therefrom so as todefine all the aforesaid elements in 3,1s9,9sa

connected relationship but in substantially flat form and which has tabswith dimensions between their inner and outer end portions which aregreater than the radial distance between said end portions, and formingsaid blanl to pitch the blades and to offset the hub section thereofaxially with respect to the tabs, said last mentioned step including thedisplacement of said tabs in such manner than the differences betweentheir said end portion-to-end portion dimensions and the said radialdistance between their end portions are employed to accommodate axialmovement of the hub section without excessive deformation and rupture ofthe aforesaid elements.

2. A method of making an integral fan and slinger ring which includes aplurality of similarly pitched circumaxially spaced air moving blades, aslinger ring disposed about the blades, a plurality of connecting tabsextending respectively between outer edge portions of the blades and theslinger ring, and a hub section substantially oifset axially withrespect to the tabs and connected with inner edge portions of theblades; said method comprising the steps of providing a one-piece sheetmetal blank which has selected portions severed therefrom so as todefine all the aforesaid elements in connected relationship but insubstantially flat form and which has tabs which extend at leastpartially out of the plane of the blank between their inner and outerend portions so as to have dimensions between said end portions whichare greater than the radial distance between the end portions, andforming said blank to pitch the blades and to offset the hub sectionthereof axially with respect to the tabs, said last mentioned stepincluding the displacement of said tabs in such manner that thedifferences between their said end portion-to-end portion dimensions andthe said radial distance between their end portions are employed toaccommodate axial movement of the hub section without excessivedeformation and rupture of the aforesaid elements.

3. A method of making an integral fan and slinger ring which includes aplurality of sirrilarly pitched circumaxially spaced air moving blades,a slinger ring disposed about the blades, a plurality of connecting tabsextending respectively between outer edge portions of the blades and theslinger ring, and a hub section substantially offset axially withrespect to the tabs and connected with inner edge portions of theblades; said method comprising the steps of providing a one-piece sheetmetal blank which has selected portions severed therefrom so as todefine all the aforesaid elements in connected relationship but in flatform and which has tabs with center lines which extend angularly betweentheir end portions with respect to radii so as to have endportion-to-end portion dimensions greater than the radial distancebetween their end portions, and forming said blank to pitch the bladesand to offset the hub section thereof axially with respect to the tabs,said last mentioned step including the displacement of said tabs in suchmanner that the differences between their said end portion-to-endportion dimensions and the said radial distance between their endportions are employed to accommodate axial movement of the hub sectionwithout excessive deformation and rupture of the aforesaid elements.

4. A method of making an integral fan and slinger ring which includes aplurality of similarly pitched circumaxially spaced air moving blades, aslinger ring disposed about the blades, a plurality of connecting tabsextending respectively between outer edge portions of the blades and theslinger ring, and a hub section substantially offset axially withrespect to the tabs and connected with inner edge portions of theblades; said method comprising the steps of providing a fiat sheet metalblank, severing selected portions from the blank to define the aforesaidelements in connected relationship but in flat form, effectivelyelongating each tab by displacing at least a portion thereof from theplane of the blank, and forming the blank to pitch the blades and tooffset the hub section thereof axially with respect to the tabs, saidlast mentioned step including the stretching and approximatestraightening of the tabs whereby the axial offset movement of the hubsection is accommodated without excessive deformation and rupture of thetabs.

5. A method of making an integral fan and slinger ring which includes aplurality of similarly pitched circumaxially spaced air moving blades, aslinger ring disposed about the blades, a plurality of connecting tabsextending respectively between outer edge portions of the lades and theslinger ring, and a hub section substantially offset axially withrespect to the tabs and connected with inner edge portions of theblades; said method comprising the steps of providing a fiat sheet metalblank, severing selected portions from the blank to define the aforesaidelements in connected relationship but in flat form, effectivelyelongating each tab by preforming the same in a bowed configurationwhich extends from the plane of the blank, and forming the blank topitch the blades and to offset the hub section thereof axially withrespect to the tabs, said last mentioned step including the stretchingand approximate straightening of the tabs whereby axial offset movementof the hub section is accommodated without excessive deformation andrupture of the tabs.

6. A method of an integral fan and slinger ring which includes aplurality of similarly pitched circumaxially spaced air moving blades, aslinger ring disposed about the blades, a plurality of connecting tabsextending respectively between outer edge portions of the blades and thestinger ring,'and a hub section substantially olfset axially withrespect to the tabs and connected with inner edge portions of theblades; said method comprising the steps of providing a flat sheet metalblank, severing selected portions from the blank to define the aforesaidelements in connected relationship but in flat form, effectivelyelongating each tab by preforming the same to a corrugated cross sectionin an axial plane, and forming the blank to pitch the blades and tooffset the hub section thereof axially with respect to the tabs, saidlast mentioned step including the stretching and approximatestraightening of the tabs whereby axial offset movement of the hubsection is accommodated without excessive deformation and rupture of thetabs.

'7. A method of making an integral fan and slinger ring which includes aplurality of similarly pitched circumaxially spaced air moving blades, aslinger ring disposed about the blades, a plurality of connecting tabsextending respectively between outer edge portions of the blades and theslinger ring, and a hub section substantially offset axially withrespect to the tabs and connected with inner edge portions of theblades; said method comprising the steps of providing a flat sheet metalblank, severing selected portions of the blank to define the aforesaidelements in connected relationship but in flat form with the tab centerlines extending angularly with respect to radii, and forming the blankto pitch the blades and to offset the hub section thereof axially withrespect to the tabs, said last mentioned step including relativerotation of the slinger ring and the blades to arrange the tab centerlines approximately on radii and to thereby effectively elongate thetabs and accommodate axial oflset movement of the hub section withoutexcessive deformation and rupture of the tabs.

8. A method of making an integral fan and slinger ring which includes aplurality of similarly pitched circumaxially spaced air moving blades, aslinger ring disposed about the blades, a plurality of connecting tabsextending respectively between outer edge portions of the blades and theslinger ring, and a hub section substantially offset axially withrespect to the tabs and connected with inner edge portions of theblades; said method comprising the steps of providing a one-piece sheetmetal blank which has selected portions severed therefrom so as todefine all the aforesaid elements in connected relationship but insubstantially flat form, displacing the metal of the blank out of theplane of the blank in a narrow annular area bounding a minimum aggregatemass of metal located between the slinger ring and hub section portionsof the blank, and forming the blank to pitch the blades and to ofisetthe hub section thereof axially with respect to the tabs, said lastmentioned step including the generally radial elongation of thedisplaced metal in said annular area to accommodate the axial tion andrupture of the aforesaid elements.

Reterences Cited by the Examiner UNITED STATES PATENTS FOREIGN PATENTS8,454 1910 Great Britain.

WHETMORE A. WILTZ, Primary Examiner.

1. A METHOD OF MAKING AN INTEGRAL FAN AND SLINGER RING WHICH INCLUDES APLURALITY OF SIMILARLY PITCHED CIRCUMAXIALLY SPACED AIR MOVING BLADES, ASLINGER RING DISPOSED ABOUT THE BLADES, A PLURALITY OF CONNECTING TABSEXTENDING RESPECTIVELY BETWEEN OUTER EDGE PORTIONS OF THE BLADES AND THESLIGNER RING, AND A HUB SECTION SUBSTANTIALLY OFFSET AXIALLY WITHRESPECT TO THE TABS AND CONNECTED WITH INNER EDGE PORTIONS OF THEBLADES; SAID METHOD COMPRISING THE STEPS OF PROVIDING A ONE-PIECE SHEETMETAL BLANK WHICH HAS SELECTED PORTIONS SEVERED THEREFROM SO AS TODEFINE ALL THE AFORESAID ELEMENTS IN CONNECTED RELATIONSHIP BUT INSUBSTANTIALLY FLAT FORM AND WHICH HAS TABS WITH DIMENSIONS BETWEEN THEIRINNER AND OUTER END PORTIONS WHICH ARE GREATER THAN THE RADIAL DISTANCEBETWEEN SAID END PORTIONS, AND FORMING SAID BLANK TO PITCH THE BLADESAND TO OFFSET THE HUB SECTION THEREOF AXIALLY WITH RESPECT TO THE TABS,SAID LAST MENTIONED STEP INCLUDING THE DISPLACEMENT OF SAID TABS IN SUCHMANNER THAN THE DIFFERENCES BETWEEN THEIR SAID END PORTION-TO-ENDPORTION DIMENSIONS AND THE SAID RADIAL DISTANCE BETWEEN THEIR ENDPORTIONS ARE EMPLOYED TO ACCOMMODATE AXIAL MOVEMENT OF THE HUB SECTIONWITHOUT EXCESSIVE DEFORMATION AND RUPTURE OF THE AFORESAID ELEMENTS.